Preparation for Pt-loaded zeolite catalysts using w/o microemulsion and their hydrocracking behaviors on fischer-tropsch product

Abstract

Pt-loaded β-type zeolite catalysts with constant Pt content (0.11 wt.%) and similar pore structure were prepared using a water-in-oil (w/o) microemulsion. The effect of Pt particle synthesis conditions using microemulsion (a type of Pt complex-forming agents and the molar ratio of complex-forming agent to Pt4+) on loaded Pt particle size was investigated. The Pt particle size of the Pt catalyst using tetraethylammonium chloride (TEAC) as a complex-forming agent with the molar TEAC/Pt ratio 10 was the minimum value (3.8 nm), and was much smaller than that (6.7 nm) prepared by the impregnation method. The utilization of the complex-forming agent of which hydrophobic groups occupied a small volume and the appropriate complex-forming agent/Pt ratio were favorable for synthesis of small Pt particles. The effect of loaded Pt particle size on the hydrocracking of the Fischer-Tropsch (FT) product was investigated using the Pt-loaded zeolite catalysts at 250 °C with an initial H2 pressure of 0.5 MPa, and reaction time of 1 h. The Pt catalyst with a Pt particle size of 4.2 nm prepared using the microemulsion exhibited the maximum corresponding jet fuel yield (30.0%), which was higher than that of the impregnated catalyst.